1. Field of Invention
This invention relates generally to heavy duty, toggle type draw latches for connecting two relatively movable members.
Some of such latches, existing on the market, are equipped with safety locking means which are such like provisions for padlock installation, hook type catches, locks requiring keys, spring hooks, rotational locking cams are either expensive to manufacturer or not reliable in heavy duty applications.
The is need for a draw latch with simple, durable, reliable secondary catch with exposed engagement which will be able to operate reliably in heavy duty applications.
2. Prior Art
The Catch with Antirelease Latch by Gunnar E. Swanson in U.S. Pat. No. 3,602,723 Proposes hook type safety catch which engagement concealed within device, such arrangement does not offer positive control of the safety latch engagement and hook type catch is not reliable in heavy duty applications
The Adjustable Toggle Latch and Safety Catch offered by Schenk in U.S. Pat. No. 4,307,906 comprises the hook formed flat spring as the safety catch mounted on the latch and engaging the latch lever. The exposed spring element of this safety locking arrangement is prone to bending in heavy duty application.
The Toggle Latch with Spring Catch presented by Conrad Gunther in U.S. Pat. No. 4,352,513 comprises spring type safety catch which is prone to bending and does not offer observable engagement.
The Handle Operated Draw Latch with Safety Catch disclosed by Weinerman et al U.S. Pat. No. 5,445,422 comprises hook type safety catch with too many complicated parts increasing cost of manufacturing and reducing reliability of performance.
The Over-center Latch disclosed by Norman Evans in U.S. Pat. No. 6,840,551 comprises safety catch which is pivotally movable in and out of engaged Position offers observable engagement, however, it requires significant angular rotation and rotating Catch Member is a cantilever extending from the pivotal point and is prone to bend and jam.
3. Objects and Advantages
Accordingly, besides the objects and advantages of the Toggle Latch described in my patent, several objects and advantages of the present invention are:    a. To provide a Draw Latch with simple, low manufacturing cost Safety Catch.    b. The Safety Catch shall be reliable and durable to withstand strong unlocking forces in heavy duty applications.    c. The Safety Catch shall have positive, observable engagement.    d. Action of the Safety catch shall be ergonomically convenient